阅读说明：本技术 带补气增焓的空气源热泵系统及其控制方法 (Air source heat pump system with air supplement and enthalpy increase functions and control method thereof ) 是由 鲜智慧 张少龙 周鸣贵 于 2020-11-27 设计创作，主要内容包括：本发明涉及空气源热泵,特别涉及带补气增焓的空气源热泵系统及其控制方法,本发明带补气增焓的空气源热泵系统及其控制方法通过改变带补气增焓的空气源热泵系统的节流元件组合,通过控制电磁阀开断来控制增加的电子膨胀阀用于主路节流还是用于补气增焓回路来实现空气热源泵对环境温度的适应,进一步,通过控制电子膨胀阀的开度步数实现对空气热源泵的精准控制,提升带补气增焓的空气热源泵的系统性能,本发明适用于带补气增焓的空气热源泵。(The invention relates to an air source heat pump, in particular to an air source heat pump system with air supplement and enthalpy increase and a control method thereof.)

1. The air source heat pump system with the air supply and enthalpy increase function is characterized by comprising a throttling element combination, wherein the throttling element combination comprises a first electronic expansion valve, a second electronic expansion valve, a first electromagnetic valve and a second electromagnetic valve; one end of the first electronic expansion valve is connected with one end of the second electronic expansion valve and is used as a first interface of the throttling element combination, the other end of the second electronic expansion valve is connected with one end of the first electromagnetic valve and one end of the second electromagnetic valve, the other end of the first electromagnetic valve is used as a second interface of the throttling element combination, and the other end of the second electromagnetic valve is connected with the other end of the first electronic expansion valve and is used as a third interface of the throttling element combination; the second interface is used for connecting a compressor air-supplying enthalpy-increasing port of the air source heat pump system with the air-supplying enthalpy-increasing function; one interface of the first interface and the third interface is connected with the use side heat exchanger, and the other interface is connected with the heat source side heat exchanger.

2. The control method of the air source heat pump system with the air supplement and enthalpy increase function is applied to the air source heat pump system with the air supplement and enthalpy increase function in claim 1, and is characterized in that the air source heat pump system with the air supplement and enthalpy increase function controls the second electronic expansion valve to be used for main path throttling or used for an air supplement and enthalpy increase loop by controlling the first electromagnetic valve and the second electromagnetic valve to be opened and closed.

3. The control method of the air source heat pump system with the air supplement and enthalpy increase function according to claim 2, characterized by comprising the following steps:

s01, presetting temperatures in the system, wherein the preset temperatures comprise a first preset temperature, a second preset temperature, a third preset temperature and a fourth preset temperature; the first preset temperature and the second preset temperature are preset temperatures in a heating mode, the first preset temperature is higher than the second preset temperature, the third preset temperature and the fourth preset temperature are preset temperatures in a cooling mode, and the third preset temperature is higher than the fourth preset temperature; setting the environment temperature Tamb greater than a first preset temperature as a first interval, setting the environment temperature Tamb not greater than the first preset temperature and not less than a second preset temperature as a second interval, setting the environment temperature Tamb less than the second preset temperature as a third interval, setting the environment temperature Tamb greater than the third preset temperature as a fourth interval, setting the environment temperature Tamb not greater than the third preset temperature and not less than the fourth preset temperature as a fifth interval, and setting the environment temperature Tamb less than the fourth preset temperature as a sixth interval;

s02, setting an upper opening limit, a lower opening limit and a standby opening degree of the first electronic expansion valve in the system; setting an upper opening limit, a lower opening limit and a standby opening degree of a second electronic expansion valve in the system; the upper limit of the opening degree of the first electronic expansion valve is not more than 500 steps, the lower limit of the opening degree of the first electronic expansion valve is more than 0 step, the standby opening degree of the first electronic expansion valve is less than the upper limit of the opening degree of the first electronic expansion valve and more than the lower limit of the opening degree of the first electronic expansion valve, the upper limit of the opening degree of the second electronic expansion valve is not more than 500 steps, the lower limit of the opening degree of the second electronic expansion valve is more than 0 step, and the standby opening degree of the second electronic expansion valve is less than the upper limit of the opening degree of the second electronic expansion valve and more than the lower limit of;

s03, disconnecting the first electromagnetic valve and the second electromagnetic valve when the system is in standby; the first electronic expansion valve is reset to a standby opening degree, and the second electronic expansion valve is reset to a standby opening degree;

s03, when the system is started, controlling the on-off states of the first electromagnetic valve and the second electromagnetic valve according to the system running mode, the size relation between the actually measured environment temperature Tamb and the system preset temperature, namely: in the heating mode, when the ambient temperature Tamb is in a first interval, the first electromagnetic valve is closed, and the second electromagnetic valve is opened; when the ambient temperature Tamb is in a second interval, the first electromagnetic valve is closed, the second electromagnetic valve is opened, and when the ambient temperature Tamb is in a third interval, the first electromagnetic valve is opened, and the second electromagnetic valve is closed; in the refrigeration mode, when the ambient temperature Tamb is in a fourth interval, the first electromagnetic valve is closed, the second electromagnetic valve is opened, when the ambient temperature Tamb is in a fifth interval, the first electromagnetic valve is closed, the second electromagnetic valve is opened, and when the ambient temperature Tamb is in a sixth interval, the first electromagnetic valve is closed, and the second electromagnetic valve is closed;

s04, when the ambient temperature Tamb changes from a first interval to a second interval, a third interval to the second interval, a fourth interval to a fifth interval or a sixth interval to the fifth interval in the operation of the system, the first electromagnetic valve keeps the last state, and the second electromagnetic valve keeps the last state; when the ambient temperature Tamb changes from the second interval to the third interval, the second interval changes to the first interval, the fifth interval changes to the fourth interval, and the fifth interval changes to the sixth interval, the first electromagnetic valve is switched to the on-off state when the interval where the ambient temperature Tamb changes is started, and the second electromagnetic valve is switched to the on-off state when the interval where the ambient temperature Tamb changes is started.

4. The control method of the air-source heat pump system with air-supplementing and enthalpy-increasing functions as claimed in claim 3, wherein in S04, when the ambient temperature is in the first interval, if the opening degree of the first electronic expansion valve reaches the lower limit value and continues to operate for a period of time, the system sets the opening degree of the second electronic expansion valve to step 0; when the environment temperature is in a fourth interval, if the opening degree of the first electronic expansion valve reaches the lower limit value and the first electronic expansion valve continues to operate for a period of time, the system closes the second electronic expansion opening degree to step 0, and when the opening degree of the first electronic expansion valve is recovered to a certain step number, the second electronic expansion valve starts from the lower limit opening degree again and enters the system circulation; when the ambient temperature is in the sixth interval, if the opening degree of the first electronic expansion valve reaches the upper limit value and lasts for a period of time, the system opens the second electromagnetic valve, and the second electronic expansion valve enters the system cycle from the lower limit opening degree.

Technical Field

The invention relates to an air source heat pump, in particular to an air source heat pump system with air supplement and enthalpy increase functions and a control method thereof.

Background

The air source heat pump can be divided into a low-ambient-temperature air source heat pump and a normal-temperature air source heat pump according to use scenes, two sets of different air source heat pumps are adopted for the two use scenes, however, the cost is too high, and the utilization rate of the two sets of air source heat pumps is not high, namely: when the temperature is low, the normal temperature air heat source pump does not work, and when the temperature is normal, the low ambient temperature air heat source pump does not work; in order to solve the above problems, in the prior art, a capillary tube and a solenoid valve are connected in parallel at an electronic expansion valve of an air heat source pump, but although the purpose that the same air heat source pump can be normally used at low ambient temperature or normal temperature can be achieved, the air heat source pump does not accurately control the capillary tube, and the capillary tube is fixed in a system after specification selection, so that the range of adapting to working condition temperature is limited, and the optimal point of refrigeration and heating is difficult to be considered; the performance of the system is low and even drops sharply, in addition, the capillary tube is more prone to risks such as ice blockage, and the reliability is lower than that of the electronic expansion valve.

Disclosure of Invention

The technical problems solved by the invention are as follows: the invention provides an air source heat pump system with air supplement and enthalpy increase and a control method thereof, which achieve the aim that the same air source heat pump can be normally used at low ambient temperature or normal temperature, further realize the accurate control of the air source heat pump on a throttling component and improve the performance of the air source heat pump with air supplement and enthalpy increase.

The invention adopts the technical scheme for solving the technical problems that: the air source heat pump system with air supplement and enthalpy increase comprises a throttling element combination, wherein the throttling element combination comprises a first electronic expansion valve, a second electronic expansion valve, a first electromagnetic valve and a second electromagnetic valve; one end of the first electronic expansion valve is connected with one end of the second electronic expansion valve and is used as a first interface of the throttling element combination, the other end of the second electronic expansion valve is connected with one end of the first electromagnetic valve and one end of the second electromagnetic valve, the other end of the first electromagnetic valve is used as a second interface of the throttling element combination, and the other end of the second electromagnetic valve is connected with the other end of the first electronic expansion valve and is used as a third interface of the throttling element combination; the second interface is used for connecting a compressor air-supplying enthalpy-increasing port of the air source heat pump system with the air-supplying enthalpy-increasing function; one interface of the first interface and the third interface is connected with the use side heat exchanger, and the other interface is connected with the heat source side heat exchanger.

Further, the control method of the air source heat pump system with the air supplement and enthalpy increase functions controls the second electronic expansion valve to be used for main path throttling or used for the air supplement and enthalpy increase loop by controlling the first electromagnetic valve and the second electromagnetic valve to be opened and closed.

Further, the control method of the air source heat pump system with the air supplementing and enthalpy increasing functions comprises the following steps:

s01, presetting temperatures in the system, wherein the preset temperatures comprise a first preset temperature, a second preset temperature, a third preset temperature and a fourth preset temperature; the first preset temperature and the second preset temperature are preset temperatures in a heating mode, the first preset temperature is higher than the second preset temperature, the third preset temperature and the fourth preset temperature are preset temperatures in a cooling mode, and the third preset temperature is higher than the fourth preset temperature; setting the environment temperature Tamb greater than a first preset temperature as a first interval, setting the environment temperature Tamb not greater than the first preset temperature and not less than a second preset temperature as a second interval, setting the environment temperature Tamb less than the second preset temperature as a third interval, setting the environment temperature Tamb greater than the third preset temperature as a fourth interval, setting the environment temperature Tamb not greater than the third preset temperature and not less than the fourth preset temperature as a fifth interval, and setting the environment temperature Tamb less than the fourth preset temperature as a sixth interval;

s02, setting an upper opening limit, a lower opening limit and a standby opening degree of the first electronic expansion valve in the system; setting an upper opening limit, a lower opening limit and a standby opening degree of a second electronic expansion valve in the system; the upper limit of the opening degree of the first electronic expansion valve is not more than 500 steps, the lower limit of the opening degree of the first electronic expansion valve is more than 0 step, the standby opening degree of the first electronic expansion valve is less than the upper limit of the opening degree of the first electronic expansion valve and more than the lower limit of the opening degree of the first electronic expansion valve, the upper limit of the opening degree of the second electronic expansion valve is not more than 500 steps, the lower limit of the opening degree of the second electronic expansion valve is more than 0 step, and the standby opening degree of the second electronic expansion valve is less than the upper limit of the opening degree of the second electronic expansion valve and more than the lower limit of;

s03, disconnecting the first electromagnetic valve and the second electromagnetic valve when the system is in standby; the first electronic expansion valve is reset to a standby opening degree, and the second electronic expansion valve is reset to a standby opening degree;

s03, when the system is started, controlling the on-off states of the first electromagnetic valve and the second electromagnetic valve according to the system running mode, the size relation between the actually measured environment temperature Tamb and the system preset temperature, namely: in the heating mode, when the ambient temperature Tamb is in a first interval, the first electromagnetic valve is closed, and the second electromagnetic valve is opened; when the ambient temperature Tamb is in a second interval, the first electromagnetic valve is closed, the second electromagnetic valve is opened, and when the ambient temperature Tamb is in a third interval, the first electromagnetic valve is opened, and the second electromagnetic valve is closed; in the refrigeration mode, when the ambient temperature Tamb is in a fourth interval, the first electromagnetic valve is closed, the second electromagnetic valve is opened, when the ambient temperature Tamb is in a fifth interval, the first electromagnetic valve is closed, the second electromagnetic valve is opened, and when the ambient temperature Tamb is in a sixth interval, the first electromagnetic valve is closed, and the second electromagnetic valve is closed;

s04, when the ambient temperature Tamb changes from a first interval to a second interval, a third interval to the second interval, a fourth interval to a fifth interval or a sixth interval to the fifth interval in the operation of the system, the first electromagnetic valve keeps the last state, and the second electromagnetic valve keeps the last state; when the ambient temperature Tamb changes from the second interval to the third interval, the second interval changes to the first interval, the fifth interval changes to the fourth interval, and the fifth interval changes to the sixth interval, the first electromagnetic valve is switched to the on-off state when the interval where the ambient temperature Tamb changes is started, and the second electromagnetic valve is switched to the on-off state when the interval where the ambient temperature Tamb changes is started.

Further, in S04, when the ambient temperature is in the first interval, if the opening degree of the first electronic expansion valve reaches the lower limit value and continues to operate for a certain period of time, the system sets the opening degree of the second electronic expansion valve to 0; when the environment temperature is in a fourth interval, if the opening degree of the first electronic expansion valve reaches the lower limit value and the first electronic expansion valve continues to operate for a period of time, the system closes the second electronic expansion opening degree to step 0, and when the opening degree of the first electronic expansion valve is recovered to a certain step number, the second electronic expansion valve starts from the lower limit opening degree again and enters the system circulation; when the ambient temperature is in the sixth interval, if the opening degree of the first electronic expansion valve reaches the upper limit value and lasts for a period of time, the system opens the second electromagnetic valve, and the second electronic expansion valve enters the system cycle from the lower limit opening degree.

The invention has the beneficial effects that: the air source heat pump system with air supplement and enthalpy increase and the control method thereof control the second electronic expansion valve to be used for main path throttling or an air supplement and enthalpy increase loop by controlling the opening and the closing of the electromagnetic valve to realize the adaptation of the air source heat pump to the ambient temperature, further realize the accurate control of the air source heat pump by controlling the opening step number of the electronic expansion valve, and improve the system performance of the air source heat pump system with air supplement and enthalpy increase.

Drawings

FIG. 1 is a combination diagram of a throttling element of an air source heat pump system with air supply and enthalpy increase and a control method thereof.

FIG. 2 is a system diagram of an air source heat pump system with air supplement and enthalpy increase and a control method thereof according to the present invention.

FIG. 3 is a system operation process of the air source heat pump system with air supplement and enthalpy increase and the control method thereof.

Detailed Description

As shown in fig. 1, the throttling element combination of the air source heat pump system with air supplement and enthalpy increase and the control method thereof of the invention comprises a first electronic expansion valve, a second electronic expansion valve, a first electromagnetic valve and a second electromagnetic valve; one end of the first electronic expansion valve is connected with one end of the second electronic expansion valve to serve as a first interface of the throttling element combination, the other end of the second electronic expansion valve is connected with one end of the first electromagnetic valve and one end of the second electromagnetic valve, the other end of the first electromagnetic valve serves as a second interface of the throttling element combination, and the other end of the second electromagnetic valve is connected with the other end of the first electronic expansion valve to serve as a third interface of the throttling element combination.

One embodiment of the air source heat pump system with air supply and enthalpy increase function of the invention is shown in figure 2, and comprises a use side heat exchanger, a four-way valve, a gas-liquid separator, a compressor, a heat source side heat exchanger, an economizer and a throttling element combination; one end of a refrigerant channel of the use side heat exchanger is connected with a four-way valve E pipeline, a four-way valve S pipeline is connected with an inlet of the air pressure separator, an outlet of the air-liquid separator is connected with an air suction port of the compressor, an air exhaust port of the compressor is connected with a four-way valve D pipeline, a four-way valve C pipeline is connected with one end of the refrigerant channel of the heat source side heat exchanger, the other end of the refrigerant channel of the heat source side heat exchanger is connected with a third interface of the throttling element combination, a second interface of the throttling element combination is connected with an auxiliary path outlet of the economizer, a first interface of the throttling element combination is connected with a main path outlet of the economizer, an auxiliary path inlet of the economizer is connected.

The control method of the air source heat pump system with the air supplement and enthalpy increase function controls the second electronic expansion valve to be used for main path throttling or an air supplement and enthalpy increase loop by controlling the first electromagnetic valve and the second electromagnetic valve to be opened and closed, and particularly the control method of the air source heat pump system with the air supplement and enthalpy increase function, which is suitable for the embodiment shown in the attached figure 2, comprises the following steps:

s01, presetting temperatures in the system, wherein the preset temperatures comprise a first preset temperature, a second preset temperature, a third preset temperature and a fourth preset temperature; the first preset temperature and the second preset temperature are preset temperatures in a heating mode, the first preset temperature is higher than the second preset temperature, the third preset temperature and the fourth preset temperature are preset temperatures in a cooling mode, and the third preset temperature is higher than the fourth preset temperature; setting the environment temperature Tamb greater than a first preset temperature as a first interval, setting the environment temperature Tamb not greater than the first preset temperature and not less than a second preset temperature as a second interval, setting the environment temperature Tamb less than the second preset temperature as a third interval, setting the environment temperature Tamb greater than the third preset temperature as a fourth interval, setting the environment temperature Tamb not greater than the third preset temperature and not less than the fourth preset temperature as a fifth interval, and setting the environment temperature Tamb less than the fourth preset temperature as a sixth interval;

s02, setting an upper opening limit, a lower opening limit and a standby opening degree of the first electronic expansion valve EXV1 in the system; setting an upper opening limit, a lower opening limit and a standby opening degree of a second electronic expansion valve in the system; the upper limit of the opening degree of the first electronic expansion valve EXV1 is not more than 500 steps, the lower limit of the opening degree of the first electronic expansion valve EXV1 is more than 0 steps, the standby opening degree of the first electronic expansion valve EXV1 is smaller than the upper limit of the opening degree of the first electronic expansion valve EXV1 and is larger than the lower limit of the opening degree of the first electronic expansion valve EXV1, the upper limit of the opening degree of the second electronic expansion valve EXV2 is not more than 500 steps, the lower limit of the opening degree of the second electronic expansion valve EXV2 is larger than 0 steps, and the standby opening degree of the second electronic expansion valve EXV2 is smaller than the upper limit of the opening degree of the second electronic expansion valve EXV2 and is larger than the lower limit of the opening;

s03, when the system is in standby, the first electromagnetic valve SV1 and the second electromagnetic valve SV2 are disconnected; the first electronic expansion valve EXV1 is reset to a standby opening degree, and the second electronic expansion valve EXV2 is reset to a standby opening degree;

s03, when the system is started, the on-off states of a first electromagnetic valve SV1 and a second electromagnetic valve SV2 are controlled according to the system running mode, the relation between the actually measured environment temperature Tamb and the preset system temperature, namely: in the heating mode, when the ambient temperature Tamb is in a first interval, the first electromagnetic valve SV1 is closed, and the second electromagnetic valve SV2 is opened; when the environment temperature Tamb is in a second interval, the first solenoid valve SV1 is closed, the second solenoid valve SV2 is opened, and when the environment temperature Tamb is in a third interval, the first solenoid valve SV1 is opened, and the second solenoid valve SV2 is closed; in the cooling mode, when the ambient temperature Tamb is in the fourth interval, the first solenoid valve SV1 is closed, the second solenoid valve SV2 is opened, when the ambient temperature Tamb is in the fifth interval, the first solenoid valve SV1 is closed, the second solenoid valve SV2 is opened, when the ambient temperature Tamb is in the sixth interval, the first solenoid valve SV1 is closed, and the second solenoid valve SV2 is closed;

s04, when the ambient temperature Tamb changes from a first interval to a second interval, a third interval to the second interval, a fourth interval to a fifth interval or a sixth interval to the fifth interval in the operation of the system, the first electromagnetic valve keeps the last state, and the second electromagnetic valve keeps the last state; when the ambient temperature Tamb changes from the second interval to the third interval, the second interval changes to the first interval, the fifth interval changes to the fourth interval, and the fifth interval changes to the sixth interval, the first electromagnetic valve is switched to the on-off state when the interval where the ambient temperature Tamb changes is started, and the second electromagnetic valve is switched to the on-off state when the interval where the ambient temperature Tamb changes is started.

Specifically, as shown in fig. 2, when the system is in a standby state, the solenoid valve is closed, the electronic expansion valve is reset, that is, the first solenoid valve SV1 and the second solenoid valve SV2 are both closed, and the first electronic expansion valve EXV1 and the second electronic expansion valve EXV2 are reset to a standby opening degree set in the system; when the system is started, the operation interval is selected according to the environment temperature and the mode, the modes are divided into 2 types, one type is heating, the other type is refrigerating, wherein the heating mode is divided into three intervals, namely: section 1, section 2, and section 3, the cooling mode is also divided into three sections, namely: and the system controls the on-off states of the first solenoid valve SV1 and the second solenoid valve SV2 according to the operation intervals, the electronic expansion valve operates according to the control logic of the selected interval, and if special conditions occur in the electronic expansion valve, the special conditions are automatically controlled according to the electronic expansion valve to be processed.

Specifically, the system operation interval and the switching state control relationship of the first solenoid valve SV1 and the second solenoid valve SV2 are as follows: when the environment temperature Tamb is in an interval 1, the first electromagnetic valve SV1 is closed, and the second electromagnetic valve SV2 is opened; when the environment temperature Tamb is in the interval 2, the first electromagnetic valve SV1 is closed, and the second electromagnetic valve SV2 is opened; when the environment temperature Tamb is in a section 3, a first electromagnetic valve SV1 is opened, and a second electromagnetic valve SV2 is closed; when the environment temperature Tamb is in a section 4, the first electromagnetic valve SV1 is closed, and the second electromagnetic valve SV2 is opened; when the environment temperature Tamb is in an interval 5, the first electromagnetic valve SV1 is closed, and the second electromagnetic valve SV2 is opened; when the environment temperature Tamb is in the interval 6, the first electromagnetic valve SV1 is closed, and the second electromagnetic valve SV2 is closed; when the ambient temperature Tamb changes from the interval 1 to the interval 2, the first solenoid valve SV1 remains closed, and the second solenoid valve SV2 remains open; when the ambient temperature Tamb changes from the interval 2 to the interval 3, the first solenoid valve SV1 is opened, and the second solenoid valve SV2 is closed; when the ambient temperature Tamb changes from the interval 3 to the interval 2, the first solenoid valve SV1 remains closed, and the second solenoid valve SV2 remains open; when the ambient temperature Tamb changes from the interval 2 to the interval 1, the first solenoid valve SV1 is closed, and the second solenoid valve SV2 is opened; when the ambient temperature Tamb changes from the interval 4 to the interval 5, the first solenoid valve SV1 remains closed, and the second solenoid valve SV2 remains open; when the environment temperature Tamb changes from the interval 5 to the interval 6, the first electromagnetic valve SV1 is closed, and the second electromagnetic valve SV2 is closed; when the ambient temperature Tamb changes from the interval 6 to the interval 5, the first solenoid valve SV1 remains closed, and the second solenoid valve SV2 remains closed; when the ambient temperature Tamb changes from interval 5 to interval 4, the first solenoid valve SV1 is closed, and the second solenoid valve SV2 is opened.

The specific special case treatment for the automatic control of the electronic expansion valve comprises the following cases: in a first special case, when the ambient temperature is in a first interval, if the opening degree of the first electronic expansion valve reaches a lower limit value and the first electronic expansion valve is continuously operated for a period of time, the system sets the opening degree of the second electronic expansion valve to 0; in a second special case, when the ambient temperature is in the fourth interval, if the opening degree of the first electronic expansion valve reaches the lower limit value and the first electronic expansion valve continues to operate for a period of time, the system keeps the second electronic expansion opening degree at step 0 until the opening degree of the first electronic expansion valve is restored to a certain number of steps, and the second electronic expansion valve starts from the lower limit opening degree again and enters the system circulation; in a third special case, when the ambient temperature is in the sixth interval, if the opening degree of the first electronic expansion valve reaches the upper limit value and lasts for a while, the system opens the second electromagnetic valve, and the second electronic expansion valve enters the system cycle starting from the lower limit opening degree.